1khz at 94db is the same spec mfrs use to measure mic sensitivity, and provides me a relatively accurate known source level for testing.

im measuring dBv (with a preamp stage at a fixed gain) not mV directly, but its pretty repeatable and trivial to measure output of caps to 0.1 dB. I'm putting together some pairs from single DPA caps (larger ones right now, sitting them right down flat on the recessed transducer). ill have to build a little mount to repeatably measure 406x s to make sure they sit in the same position in there. ive got the little insert i can modify, i was thinking some u-shaped foam to hold the 406x by the cable so its head sticks into a sealed chamber. i think if i do this and take repeat measurements (unmounting and re-mounting it) i should be able to get over any variation from mislocation of the capsule

you can borrow it if you want ill have limited use for it once im done doing my testing

with 4011 capsule:

« Last Edit: May 16, 2019, 02:16:07 AM by jerryfreak »

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team schoeps, dpa, benchmark, and zoom mostly... subject to change without warning

i flipped the adapter bushing upside down to test my CORE 4099 pair (mics purchased separately). Was astonished that they are very closely matched, <0.5 dB in multiple tests, very good! the stereo sets of 4099 they sell for double mic'ing pianos are matched to +/- 1.5 dB so i got lucky.....

my larger caps arent so close, about 1-1.5 dB apart

« Last Edit: May 16, 2019, 03:59:10 AM by jerryfreak »

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team schoeps, dpa, benchmark, and zoom mostly... subject to change without warning

Jerryfreak those calibrators are very finicky about how well you seal the transducer in the collar and how far away the capsule’s membrane is from the transducer. I’m sure you are being careful and trying to be repeatable, but if you are not using a mount specifically made for the calibrator and mics you are testing, I’m not sure you can be confident in 0.5dB differences. Using it for directional mics is, as mentioned above, not a valid test.

Those Dayton Audio measurement mics look like they come from the same Chinese factory as the ones Behringer used to (still?) sell. Good value for a decently flat mic. You need a calibrator like the one Jerryfreak has to match their wild sensitivity differences if you want to match pairs or more. I ran 6 of those into a multiplexer for a few years before building a custom measurement set up using matched Primo EM72 capsules with calibration files.

An easy way to insure you place the mics in front of the source signal speaker in the same spot everytime, is to use a tight string stretched across the test area at the same height as the tweeter. Put a marker dot on the string right where you want to place each of the capsules. Place the capsules touching the dot on the string behind their grille. Just don’t bump into the string mounts. You can get more complicated with laser pointers etc...

I’d like to see some of the impulse responses and freq responses when you start to take them. Good luck!

I run DPA4060 >> homemade 9V BB >> R09HR LINE IN all the time with my Jecklin disc and it works perfect for a wide range of music and loudness levels. Output at Max SPL (134dBSPL) is 2Vrms. That’s line level in my book. . Hard to beat the size vs quality of this set up.